Fig. 2689.
There are many different methods of lacing a belt, but those here described are generally preferred. Thus referring to [Fig. 2687] the lace is first passed through holes g and d, the ends being of equal length from the belt and emerging on the side that is to be the outside of the belt, thence each end of the lace is laced towards the edge of the belt, the dotted lines in the cut showing the path of the lace. It is then laced back to the middle of the belt, the second inside lacing exactly overlaying the first, the laces never crossing; the outside appearing as in [Fig. 2688]. The ends are in some cases tied in a knot on the outside, and in others fastened as shown in [Fig. 2689], in which case the ends are merely held by friction, which will serve very well unless for a belt that is tightly strained.
By this method of lacing all the crossing of the lace is on the outside of the belt, which is an advantage, because from the creep of the belt the lace undergoes considerable friction, which is apt to rapidly wear out the lace, especially if it be crossed on the side of the bed that meets the pulley surface.
Fig. 2690.
[Fig. 2690] shows a method of lacing in which the crossing of the lace is entirely avoided, the knot being on the outside at a a. The path of the lace on one side of the belt is shown in full lines, and on the other side in dotted lines.
The objections to lacing are that the lace lifts the belt from the pulley surface, which throws all the wear on the lace, causing it eventually to break, and which also reduces the area of belt (at the joint) in contact with the pulley surface and reduces the driving power of the belt at the time the joint is passing over the pulley. In fact, in running belts this reduction of transmitting capacity is not great, because of the rapidity with which the joint passes over the pulley, but in slow moving belts slip is very apt to occur when the lace meets the pulley, especially if the power transmitted is great in proportion to the width of the belt.